Phosphine ligands with chiral centers on carbon and phosphorous atoms are known in the art. A particular class of phosphine ligands is constituted of those linked by a bridge of three carbon atoms, i.e. 1,3-diphosphine ligands. Examples of 1,3-diphosphine ligands with one or two chiral centers on the carbon atoms of the bridge are SKEWPHOS (A) and CHAIRPHOS (B) see J. Am. Chem. Soc. 1981, 103, 2273. Another type of chiral phosphine ligands are those where the P atom is contained in a phospholane ring such as for example in the BPE ligand (C), described in Tetrahedron Asymmetry, 1991, 2,(7), 569, or in compound D, described in Angew. Chem. Int. Ed. 2002, 41(9), 1612.

The objective of the present invention is to provide further chiral 1,3-diphosphine ligands with one or two chiral centers on carbon atoms of the bridge and one chiral center on the phosphorus atom, i.e. a new bidentate C,P-chiral 1,3-diphosphine ligand system which form fairly rigid bicyclo[4.3.0]nonane type chelates with transition metals. The process for synthesizing such new ligand is part of the present invention; it has the advantage of being very short as shown in Scheme 1.